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1.
bioRxiv ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-39005441

ABSTRACT

Marfan Syndrome (MFS) is a connective tissue disorder due to mutations in fibrillin-1 ( Fbn1 ), where a Fbn1 missense mutation ( Fbn1 C1039G/+ ) can result in systemic increases in the bioavailability and signaling of transforming growth factor-ß (TGF-ß). In a well-established mouse model of MFS ( Fbn1 C1041G/+ ), pre-mature aging of the aortic wall and the progression of aortic root aneurysm are observed by 6-months-of-age. TGF-ß signaling has been implicated in cerebrovascular dysfunction, loss of blood-brain barrier (BBB) integrity, and age-related neuroinflammation. We have reported that pre-mature vascular aging in MFS mice could extend to cerebrovasculature, where peak blood flow velocity in the posterior cerebral artery (PCA) of 6-month-old (6M) MFS mice was reduced, similarly to 12-month-old (12M) control mice. Case studies of MFS patients have documented neurovascular manifestations, including intracranial aneurysms, stroke, arterial tortuosity, as well as headaches and migraines, with reported incidence of pain and chronic fatigue. Despite these significant clinical observations, investigation into cerebrovascular dysfunction and neuropathology in MFS remains limited. Using 6M-control ( C57BL/6 ) and 6M-MFS ( Fbn1 C1041G/+ ) and healthy 12M-control male and female mice, we test the hypothesis that abnormal Fbn1 protein expression is associated with altered cerebral microvascular density, BBB permeability, and neuroinflammation in the PCA-perfused hippocampus, all indicative of a pre-mature aging brain phenotype. Using Glut1 staining, 6M-MFS mice and 12M-CTRL similarly present decreased microvascular density in the dentate gyrus (DG), cornu ammonis 1 (CA1), and cornu ammonis 3 (CA3) regions of the hippocampus. 6M-MFS mice exhibit increased BBB permeability in the DG, CA1, and CA3 as evident by Immunoglobulin G (IgG) staining, which was more comparable to 12M-CTRL mice. 6M-MFS mice show a higher number of microglia in the hippocampus compared to age-matched control mice, a pattern resembling that of 12M-CTRL mice. This study represents the first known investigation into neuropathology in a mouse model of MFS and indicates that the pathophysiology underlying MFS leads to a systemic pre-mature aging phenotype. This study is crucial for identifying and understanding MFS-associated neurovascular and neurological abnormalities, underscoring the need for research aimed at improving the quality of life and managing pre-mature aging symptoms in MFS and related connective tissue disorders.

4.
Spinal Cord ; 42(2): 117-23, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14765145

ABSTRACT

STUDY DESIGN: A case report of thoracic spinal cord compression in a 34-year-old male with beta-thalassemia is reported. OBJECTIVES: In patients with thalassemia, neurologic complaints should lead to a high index of suspicion for spinal cord compression from marrow expansion, ectopic bone formation and resultant stenosis. Initial presentation, diagnosis, radiographic findings, surgical treatment and follow-up are reviewed. SETTING: This case is reported from Chicago, Illinois. METHOD: A chart review is performed for the purposes of this case report. RESULTS: Patient underwent decompressive laminectomy with good surgical outcome. CONCLUSION: Rapid diagnosis and treatment of such a condition is essential to optimize the chances of recovery.


Subject(s)
Choristoma/complications , Hematopoiesis, Extramedullary/physiology , Spinal Cord Compression/diagnosis , Spinal Cord Compression/etiology , Spinal Cord/pathology , Thoracic Vertebrae/pathology , beta-Thalassemia/complications , Adult , Bone Marrow/pathology , Bone Marrow/physiopathology , Choristoma/diagnosis , Choristoma/diagnostic imaging , Dexamethasone/therapeutic use , Humans , Laminectomy , Magnetic Resonance Imaging , Male , Recovery of Function/physiology , Regional Blood Flow/physiology , Spinal Canal/diagnostic imaging , Spinal Canal/pathology , Spinal Cord/diagnostic imaging , Spinal Cord/physiopathology , Spinal Cord Compression/diagnostic imaging , Thoracic Vertebrae/physiopathology , Tomography, X-Ray Computed , Treatment Outcome
5.
J Mol Biol ; 313(1): 197-214, 2001 Oct 12.
Article in English | MEDLINE | ID: mdl-11601856

ABSTRACT

Here, a protein atom-ligand fragment interaction library is described. The library is based on experimentally solved structures of protein-ligand and protein-protein complexes deposited in the Protein Data Bank (PDB) and it is able to characterize binding sites given a ligand structure suitable for a protein. A set of 30 ligand fragment types were defined to include three or more atoms in order to unambiguously define a frame of reference for interactions of ligand atoms with their receptor proteins. Interactions between ligand fragments and 24 classes of protein target atoms plus a water oxygen atom were collected and segregated according to type. The spatial distributions of individual fragment - target atom pairs were visually inspected in order to obtain rough-grained constraints on the interaction volumes. Data fulfilling these constraints were given as input to an iterative expectation-maximization algorithm that produces as output maximum likelihood estimates of the parameters of the finite Gaussian mixture models. Concepts of statistical pattern recognition and the resulting mixture model densities are used (i) to predict the detailed interactions between Chlorella virus DNA ligase and the adenine ring of its ligand and (ii) to evaluate the "error" in prediction for both the training and validation sets of protein-ligand interaction found in the PDB. These analyses demonstrate that this approach can successfully narrow down the possibilities for both the interacting protein atom type and its location relative to a ligand fragment.


Subject(s)
DNA Ligases/chemistry , DNA Ligases/metabolism , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Peptide Library , Viral Proteins , Algorithms , Bayes Theorem , Binding Sites , DNA Ligases/genetics , Ligands , Models, Molecular , Normal Distribution , Peptide Fragments/genetics , Probability , Protein Binding
6.
Bone Marrow Transplant ; 27(9): 989-98, 2001 May.
Article in English | MEDLINE | ID: mdl-11436111

ABSTRACT

This study determined the effects of high-dose chemotherapy (HDCT) with autologous blood stem cell transplantation (ASCT) on quality of life (QL) in women with metastatic breast cancer prior to, and during treatment, and up to 1-year post-ASCT. Thirty-three women diagnosed with metastatic breast cancer participated in a phase 1 clinical trial of a new combination of cyclophosphamide (CTX) and mitoxantrone (MXT), with dose escalation of paclitaxel. Longitudinal QL data were collected using the functional living index-cancer (FLIC) and symptom scales at seven time periods: pre-induction chemotherapy (CT), post-induction CT, post-high dose CT (HDCT), and at 3, 6, 9 and 12 months post-ASCT. FLIC scores indicated that the worst problems for patients were feelings of hardship on themselves and their families, followed by psychological functioning and physical functioning problems. The time around diagnosis of the metastatic disease and following HDCT were the worst times for all levels of quality of life, but anxiety and depression symptoms continued to increase in severity across the entire follow-up period. The symptoms that were most problematic were worry about the future, loss of sexual interest, anxiety about the treatment, general worrying, and joint pain. These data highlight the problems that women with metastatic breast cancer encounter at different stages of the disease and treatment process, and can be used to tailor psychosocial interventions appropriate for treating the relevant issues at different points in time.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Breast Neoplasms/pathology , Breast Neoplasms/psychology , Hematopoietic Stem Cell Transplantation/psychology , Adolescent , Adult , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/standards , Anxiety/etiology , Arthralgia/etiology , Bone Neoplasms/psychology , Bone Neoplasms/secondary , Cyclophosphamide/administration & dosage , Depression/etiology , Female , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Liver Neoplasms/psychology , Liver Neoplasms/secondary , Longitudinal Studies , Lung Neoplasms/psychology , Lung Neoplasms/secondary , Middle Aged , Mitoxantrone/administration & dosage , Paclitaxel/administration & dosage , Quality of Life , Surveys and Questionnaires , Time Factors , Transplantation, Autologous/psychology
7.
Leuk Res ; 24(10): 805-12, 2000 Oct.
Article in English | MEDLINE | ID: mdl-10996198

ABSTRACT

We investigated whether a known T cell modulator, Cyclosporin A (CyA) is also toxic to chronic lymphocytic leukemia (B-CLL), in vitro. In contrast to seven other drugs and two types of irradiation the dose-response curves for CyA were very steep among the 36 CLL patients investigated, and the intraindividual variation of ID(80) values was remarkably lower. The mode of CyA-induced cell death was 'apoptotic-like' as indicated by flow cytometric analysis, revealing cell condensation and annexin positivity. The partially smeary DNA fragmentation pattern together with the relatively slow process of cell death revealed a distinctive pattern of cell death in CLL. Leukemia cells from patients at an advanced clinical stage, of a diffuse histologic type and showing fast progression were the most sensitive to CyA. These new observations may have therapeutic implications in CLL.


Subject(s)
Cyclosporine/pharmacology , Immunosuppressive Agents/pharmacology , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Aged , Cell Death/drug effects , Dose-Response Relationship, Drug , Female , Flow Cytometry , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Middle Aged
8.
Biosystems ; 57(1): 37-48, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10963864

ABSTRACT

In this paper, we compare the performance of two iterative clustering methods when applied to an extensive data set describing strains of the bacterial family Enterobacteriaceae. In both methods, the classification (i.e. the number of classes and the partitioning) is determined by minimizing stochastic complexity. The first method performs the minimization by repeated application of the generalized Lloyd algorithm (GLA). The second method uses an optimization technique known as local search (LS). The method modifies the current solution by making global changes to the class structure and it, then, performs local fine-tuning to find a local optimum. It is observed that if we fix the number of classes, the LS finds a classification with a lower stochastic complexity value than GLA. In addition, the variance of the solutions is much smaller for the LS due to its more systematic method of searching. Overall, the two algorithms produce similar classifications but they merge certain natural classes with microbiological relevance in different ways.


Subject(s)
Algorithms , Bacteria/classification , Cluster Analysis , Enterobacteriaceae/classification , Stochastic Processes
9.
Haematologica ; 85(8): 806-13, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10942926

ABSTRACT

BACKGROUND AND OBJECTIVES: A major obstacle to the successful use of chemotherapy in the treatment of leukemia and other cancers is the emergence of drug resistance. One of the most studied resistance mechanisms is mediated by P-glycoprotein, which can be modulated by calcium channel blockers. Here we investigated whether the Ca(2+) channel blockers verapamil and nifedipine are toxic alone and in combination with P-glycoprotein-independent anticancer drugs against chronic lymphocytic leukemia (CLL) cells in vitro. DESIGN AND METHODS: Verapamil cytotoxicity was investigated in peripheral blood samples of 35 patients with B-cell CLL and 10 healthy control subjects. Cytotoxicity was assessed in in vitro 4-day cultures using 14C-leucine incorporation as an indicator of cell viability. Interactions were tested with Ca2+ channel blockers and cyclosporine or 7 anticancer drugs: (i) chlorambucil, (ii) 2-chlorodeoxyadenosine, (iii) cisplatin, (iv) fludarabine, (v) prednisolone, (vi) adriamycin, and (vii) vincristine. The mode of cell death was assessed by annexin binding and DNA ladder formation. RESULTS: Verapamil induced dose- and time -dependent death of CLL cells in vitro. A statistically significant effect (p = 0.0085) was noted with as little as 4 microM verapamil. The mode of cell death was apoptotic as determined by annexin positivity and condensation of verapamil-treated cells. Verapamil effectively potentiated the toxicity of cyclosporine and all the anticancer drugs mentioned above. Furthermore, nifedipine, a more specific L-type calcium channel antagonist, significantly potentiated the effect of chlorambucil against CLL cells. Interpretation and Conclusions. Calcium channel blockers enhance the effect of P-glycoprotein-independent anticancer drugs remarkably. This indicates that the death signals initiated by calcium depletion and anticancer drugs together facilitate cell death. This novel finding opens a new avenue to modulate, by using calcium channel antagonists, the effect of traditional anticancer drugs having different mechanisms of P-glycoprotein-independent action.


Subject(s)
Antineoplastic Agents/pharmacology , B-Lymphocytes/drug effects , Calcium Channel Blockers/pharmacology , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Nifedipine/pharmacology , Verapamil/pharmacology , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Adult , Aged , Apoptosis/drug effects , Calcium/physiology , Calcium Signaling/drug effects , Chlorambucil/pharmacology , Cisplatin/pharmacology , Cladribine/pharmacology , Cyclosporine/pharmacology , DNA Fragmentation , Doxorubicin/pharmacology , Drug Synergism , Female , Flow Cytometry , Humans , Male , Middle Aged , Prednisolone/pharmacology , Tumor Cells, Cultured/drug effects , Vidarabine/analogs & derivatives , Vidarabine/pharmacology , Vincristine/pharmacology
10.
Eur J Haematol ; 65(1): 32-9, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10914937

ABSTRACT

Drug resistance is a major problem in chemotherapy of chronic lymphocytic leukemia (CLL). The genetic basis and molecular pathogenesis of drug resistance in CLL remain poorly understood. Here, we have investigated the association between chromosomal aberrations and cellular resistance of CLL cells against seven drugs, gamma and ultraviolet irradiation. Samples were obtained from 35 patients having a classical form of B-CLL. Chromosomal aberrations were first analyzed by traditional karyotyping improved by using optimized mitogen combinations. DNA sequence copy number changes throughout the genome were next screened by comparative genomic hybridization. Finally, fluorescence in situ hybridization was used to detect trisomy 12 and loss of Rb and deletions at chromosome 11. The cellular sensitivity in vitro was assessed by the reduction of macromolecular protein synthesis measured as incorporation of radioactive L-leucine as an endpoint. The overall analysis disclosed a statistically highly significant difference in cellular drug resistance between patients having at least three aberrations compared with patients with fewer or no aberrations. This strongly indicates that complex rather than simple molecular mechanisms are responsible for the drug and irradiation resistance in CLL. According to published results, complex aberrations are constantly associated with poor prognosis in CLL. We demonstrated here that complex chromosomal aberrations were associated with cellular irradiation and drug resistance, which, on the other hand, may be responsible for the poor clinical outcome in CLL.


Subject(s)
Chromosome Aberrations , Drug Resistance, Neoplasm/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Radiation Tolerance/genetics , Aged , Antineoplastic Agents/pharmacology , Chromosomes, Human, Pair 11/genetics , Chromosomes, Human, Pair 11/ultrastructure , Chromosomes, Human, Pair 12 , DNA, Neoplasm/genetics , Disease Progression , Female , Gamma Rays , Gene Deletion , Genes, Retinoblastoma , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Loss of Heterozygosity , Male , Middle Aged , Mitogens/pharmacology , Neoplasm Proteins/biosynthesis , Nucleic Acid Hybridization , Prognosis , Trisomy , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/radiation effects , Ultraviolet Rays
11.
Haematologica ; 85(6): 600-6, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10870116

ABSTRACT

BACKGROUND AND OBJECTIVE: The growth of B-cell chronic lymphocytic leukemia (B-CLL) cells has been shown to be dependent on exogenous growth factors in vitro. We wanted to evaluate the clinical relevance of interleukin (IL)-6, IL-1 beta and interleukin-1 receptor antagonist (IL-1Ra) in B-CLL. As the plasma levels of IL-6, IL-1 beta and IL-1Ra have been suggested to be partly dependent on gene polymorphism, the previously described polymorphisms of the IL-1 complex genes and the IL-6 gene were also studied. DESIGN AND METHODS: The plasma levels of these cytokines were measured in a cohort of 36 patients with B-CLL and in 400 healthy subjects. The previously described polymorphisms of the IL-1 complex genes and the IL-6 gene were studied using PCR and RFLP. These data was correlated with other parameters associated with severity and prognosis of B-CLL and a number of clinical and laboratory findings. RESULTS: The plasma concentrations of IL-1 beta and IL-1Ra were lower in B-CLL patients than in normal controls (p < 0.001). The IL-1 beta plasma levels were dependent on the cell immunophenotype score and state of progression of the disease. Moreover, plasma concentrations of IL-6 were elevated in B-CLL patients compared with healthy subjects (p < 0.005) and correlated with disease stage, hemoglobin levels, anemia and erythrocyte sedimentation rate in the patients. The allele frequencies of the analyzed genes were similar in patients and controls. INTERPRETATION AND CONCLUSIONS: Our data demonstrate that in B-CLL, plasma levels of IL-1 beta, IL-1Ra and IL-6 differ from normal, and mechanisms other than allelic imbalance of their genes account for the distinct cytokine profiles observed in this disease.


Subject(s)
Cytokines/blood , Leukemia, Lymphocytic, Chronic, B-Cell/blood , Sialoglycoproteins/blood , Aged , Alleles , Antirheumatic Agents/blood , Cytokines/genetics , Female , Gene Frequency , Humans , Interleukin 1 Receptor Antagonist Protein , Interleukin-1/blood , Interleukin-1/genetics , Interleukin-6/blood , Interleukin-6/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Male , Middle Aged , Polymorphism, Genetic , Prognosis
12.
Eur J Haematol ; 65(6): 370-8, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11168494

ABSTRACT

The cytotoxicity of vincristine in vitro was investigated in B chronic lymphocytic leukemia (CLL) cells and in normal peripheral blood mononuclear cells. An approximately 25-fold selectivity towards leukemic vs. normal lymphocytes was demonstrated. Cells from patients having a mature subtype (CLL or CLL/mix) or a slowly progressing form of CLL were significantly more sensitive to vincristine in vitro than the cases with a CLL/PL phenotype or faster-progressing disease. Depending on the vincristine dose, the number of dead CLL cells accumulated slowly during the 4-d observation period. Our data indicate a marked individual variation in vincristine susceptibility among individual CLL cells. Vincristine induced annexin positivity, nuclear blebbing and DNA fragmentation in CLL cells. These indicate an "apoptosis-like" cell death. Since CLL cells are in the G0/G1 phase of the cell cycle, the only known mode of anticancer action of vinca alkaloids, i.e. anti-mitotic action, cannot explain the death of CLL cells. Furthermore, similar cellular uptake and efflux of vincristine by normal and CLL cells excluded pharmacokinetic differences as a cause of selectivity of vincristine towards leukemic lymphocytes. Immunostaining of filamentous structures of CLL cells revealed that vincristine brings about selective changes in alpha-tubulin but not in beta-actin or vimentin. Although the antitubulin action of vinca alkaloids in the biochemical sense is well demonstrated, this kind of anticancer effect has not previously been shown. Vincristine is used in several regimens for CLL, but its efficacy in CLL has never been demonstrated in a clinical context and its value in routine CLL chemotherapy has been questioned. The present data strongly support the need for further evaluation of the role and mode of action of vincristine in chemotherapy of CLL and other cancers as well.


Subject(s)
Antineoplastic Agents, Phytogenic/toxicity , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Vincristine/toxicity , Aged , Annexin A5/metabolism , Antineoplastic Agents, Phytogenic/pharmacokinetics , Apoptosis/drug effects , Cytoskeletal Proteins/drug effects , DNA Fragmentation/drug effects , Dose-Response Relationship, Drug , Electrophoresis, Agar Gel , Female , Flow Cytometry , Humans , Leucine/pharmacokinetics , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Leukocytes, Mononuclear/drug effects , Male , Microscopy, Fluorescence , Middle Aged , Time Factors , Vincristine/pharmacokinetics
13.
Mutat Res ; 448(1): 1-9, 2000 Mar 14.
Article in English | MEDLINE | ID: mdl-10751617

ABSTRACT

The kinetics of UV- (254 nm) irradiation-induced DNA single-strand breaks (SSBs), generated during the excision repair of UV-induced DNA damage, in leukemic lymphocytes and in normal blood mononuclear cells (MNCs) were studied using the alkaline comet assay. The cells were isolated by density gradient centrifugation from peripheral blood of patients with chronic lymphocytic leukemia (CLL) and from healthy study subjects. The cytotoxicity of UV irradiation was determined in vitro in peripheral blood mononuclear lymphocytes from 36 CLL patients and from eight healthy donors using the incorporation of radioactive leucine in 4-day cultures. A remarkable difference in excision repair capability was observed between normal and leukemic lymphocytes. In contrast to normal lymphocytes, there was always a subpopulation of CLL cells that did not complete the repair of UV-induced DNA damage during the 24-h repair period. Furthermore, differences were also recorded between UV-sensitive and UV-resistant CLL cases. The differences in DNA migration between the maximum increase (59-77 microm) and that at 24 h after irradiation (21-66 microm) was statistically significant in two of three patients exhibiting UV-resistance. Correspondingly, only in one of three patients exhibiting UV-sensitivity was the difference in DNA migration statistically significant (maximum increase: 44-107 microm, vs. 24 h after: 42-100 microm). Our results confirm an abnormal pattern of the CLL cell response to UV irradiation. Furthermore, we identified defective processing of UV-induced DNA damage in CLL versus normal lymphocytes, particularly in UV-sensitive cases.


Subject(s)
DNA Repair/genetics , DNA Repair/radiation effects , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/radiotherapy , Adult , Aged , Apoptosis/radiation effects , Comet Assay/methods , DNA, Single-Stranded/radiation effects , Female , Humans , Kinetics , Leukocytes, Mononuclear/radiation effects , Lymphocytes/radiation effects , Male , Middle Aged , Radiation Tolerance , Ultraviolet Rays
14.
Hematol Cell Ther ; 41(3): 95-103, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10456439

ABSTRACT

Gamma-irradiation-induced DNA single- and double-strand break (SSB and DSB) formation and their repair kinetics in normal hematopoietic cells and in leukemic lymphocytes was investigated using alkaline and neutral comet assays. The cells were isolated by density gradient centrifugation from peripheral blood of patients with chronic lymphocytic leukemia (CLL) and from healthy study subjects. Furthermore, CD34+ progenitor cells isolated with immunomagnetic beads from bone marrow of non-leukemic persons were investigated. The cytotoxicity of 137Cs irradiation was determined in vitro in peripheral blood mononuclear lymphocytes from 36 CLL patients and from 8 healthy donors using radioactive leucine incorporation assay in 4-day culture. A dose-dependent increase in DNA migration was observed in alkaline (SSBs) and neutral (DSBs) gel electrophoresis when the cells were exposed to gamma-irradiation doses up to 10.4 Gy. After irradiation with doses of 2.4 and 5.4 Gy, the cells repaired their single- and double-strand breaks almost completely. The formation and repair of DNA strand breaks were essentially similar in all normal cell populations investigated and in CLL cells. The gamma-irradiation-induced cytotoxicity did not correlate with DNA strand break formation and repair capacity. According to these results, the differences of gamma-irradiation tolerance among individual CLL cases and among healthy persons are explicable in terms other than DNA strand break formation or repair.


Subject(s)
DNA Damage/radiation effects , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Aged , Antigens, CD34 , Cell Death/radiation effects , DNA/radiation effects , DNA Repair , DNA, Single-Stranded/radiation effects , Dose-Response Relationship, Radiation , Female , Hematopoietic Stem Cells/radiation effects , Humans , Leukocytes, Mononuclear/radiation effects , Lymphocytes/radiation effects , Male , Middle Aged , Radiation Tolerance
15.
Leuk Res ; 23(3): 277-9, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10071081

ABSTRACT

The chemosensitivity of leukemia cells, obtained from the peripheral blood of 35 patients with B-cell chronic lymphocytic leukemia, was determined by a leucine-incorporation assay in vitro. There was good correlation between the sensitivities to two purine analogs, 2-chlorodeoxyadenosine and 9-beta-D-arabinofuranosyl-2-fluoroadenine among previously untreated patients when tested at the 80% inhibition level. Previous exposure to chlorambucil did not affect the sensitivity to these compounds.


Subject(s)
Antineoplastic Agents/pharmacology , Cladribine/pharmacology , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Vidarabine/analogs & derivatives , Cells, Cultured , Humans , Vidarabine/pharmacology
16.
Bull Math Biol ; 61(1): 85-111, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10071511

ABSTRACT

In this paper we give a mathematically precise formulation of an old idea in bacterial taxonomy, namely cumulative classification, where the taxonomy is continuously updated and possibly augmented as new strains are identified. Our formulation is based on Bayesian predictive probability distributions. The criterion for founding a new taxon is given a firm theoretical foundation based on prediction and it is given a clear-cut interpretation. We formulate an algorithm for cumulative classification and apply it to a large database of bacteria belonging to the family Enterobacteriaceae. The resulting taxonomy makes microbiological sense.


Subject(s)
Bacteria/classification , Bayes Theorem , Databases, Factual , Enterobacteriaceae/classification , Models, Statistical
17.
Haemophilia ; 5 Suppl 2: 72-4, 1999 May.
Article in English | MEDLINE | ID: mdl-23401907

ABSTRACT

The Finnish Red Cross Blood Transfusion Service has served as the national reference laboratory for haemostasis for more than 40 years and remains still the only one in the country to diagnose inherited coagulation factor deficiencies. By September 1997, 1076 patients with von Willebrand disease (vWD) were registered. The severity of bleeding symptoms leading to diagnosis varied according to the type of vWD. After prepubertal phase distinctly more female than male patients were diagnosed. The prevalence of severe type 3 vWD is 4:1 000 000.


Subject(s)
von Willebrand Diseases/epidemiology , Adolescent , Adult , Child , Female , Finland/epidemiology , Humans , Male , Young Adult , von Willebrand Diseases/classification
18.
Eur J Cancer ; 34(7): 1008-14, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9849448

ABSTRACT

The aim of this phase I study was to determine the dose limiting toxicity (DLT), maximum tolerated dose (MTD) and efficacy of a new combination of cyclophosphamide (6 g/m2), mitoxantrone (70 mg/m2), with dose escalation of paclitaxel (TaxolR) at a starting dose of 250 mg/m2 given intravenously over 3 h in a transplantation setting. Patients with metastatic breast cancer and chemosensitive disease were eligible. The autologous blood stem cell re-infusion and subsequent recovery occurred in an out-patient setting. 50 patients were enrolled, but 10 withdrew. 40 completed the entire protocol. At 400 mg/m2 paclitaxel administered over 3 h, 3 of 6 patients experienced serious adverse events: approximately 20-40 min after completion of infusion, diaphoresis, bradycardia mild hypotension and diarrhoea occurred; 2 patients lost consciousness for a few minutes. An extended infusion schedule delivering 400 mg/m2 paclitaxel over 6 h rather than 3 h was initiated at this level without patients experiencing this DLT. At the next dose of 450 mg/m2 paclitaxel over 6 h, the same DLT was seen as at 400 mg/m2 paclitaxel over 3 h and, therefore, MTD was reached. Time to recovery for the absolute neutrophil count > or = 0.5 x 10(9)/l was 10-19 days (median 12 days); and for platelets > or = 20 x 10(9)/l was 18-20 days (median 11.5 days). 21 patients developed neutropenic fever that required intravenous antibiotics and re-admission; the transfusion frequency for packed red blood cell was 0-5 units (median 2 units) and for platelets, 1-5 encounters (median 2). 13 complete responses, 1 patient with no evidence of disease and 19 partial remissions were documented. The dose of 400 mg/m2 at an infusion rate of 6 h will be used for the ongoing phase II study to evaluate efficacy and toxicity further.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/secondary , Breast Neoplasms/therapy , Hematopoietic Stem Cell Transplantation/methods , Adult , Cyclophosphamide/administration & dosage , Cyclophosphamide/adverse effects , Disease-Free Survival , Female , Humans , Infusions, Intravenous , Middle Aged , Mitoxantrone/administration & dosage , Mitoxantrone/adverse effects , Paclitaxel/administration & dosage , Paclitaxel/adverse effects , Survival Analysis , Treatment Outcome
19.
Am J Hematol ; 59(2): 156-60, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9766801

ABSTRACT

Elderly patients with intermediate- or high-grade non-Hodgkin's lymphoma have a worse outcome than those who are younger than 60 years. It has been shown that aggressive combination chemotherapy is poorly tolerated in older patients resulting in a subsequent decrease in dose intensity. A phase II trial was conducted with mitoxantrone, prednimustine, and vincristine (NSO) in this group of patients. NSO consists of mitoxantrone 12 mg/M2 intravenously on day one, vincristine 1.4 mg/M2 intravenously on day 1 (maximum dose of two mg), and prednimustine 100 mg/M2 orally once a day for four days. NSO was repeated every 21 days. Thirty-six patients were able to be evaluated. There were 18 males and 18 females with the median age of 71 (range 60-85). NSO was well tolerated and nonhematological toxicities were uncommon. More than 80% of the patients received 90% or greater of the intended dose. The complete response rate was 60.6% and partial response was 21.8%. At 60 months the Kaplan-Meier estimate of progression-free survival was 47.9% (standard error 8.6%) and actual survival was 40.6% (standard error 8.8%). There were no differences in outcome between those with performance status (PS) of zero or one and those with PS > 1. NSO is well tolerated by elderly patients including those with PS > 1. These results compare favorably with other combinations in elderly patients with aggressive non-Hodgkin's lymphoma.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Lymphoma, Non-Hodgkin/drug therapy , Mitoxantrone/administration & dosage , Prednimustine/administration & dosage , Vincristine/administration & dosage , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/toxicity , Female , Humans , Lymphoma, Non-Hodgkin/mortality , Male , Middle Aged , Mitoxantrone/toxicity , Prednimustine/toxicity , Remission Induction , Survival Rate , Treatment Outcome , Vincristine/toxicity
20.
Comput Methods Programs Biomed ; 56(1): 11-22, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9617523

ABSTRACT

In this paper we propose a method of constructing a hierarchical classification based on the notion of stochastic complexity. Minimization of stochastic complexity amounts to maximization of the information content of the classification. A dendrogram is obtained by first finding the classification which minimizes stochastic complexity and then by step-wise merging of groups such that at each step there is a minimum loss of information. The method was applied to a database containing 5313 strains of Enterobacteriaceae. The results are in reasonable accordance with present-day views on the taxonomy of Enterobacteriaceae.


Subject(s)
Enterobacteriaceae/classification , Stochastic Processes
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